In a production procedure of a display device, generally, some abnormal subpixels are produced due to out-of-flatness of glass plate and problems occurred in fabricating process. Driven by a data voltage, an actual grayscale value represented by the abnormal subpixel is different from a display grayscale value corresponding to the data voltage, that is, there occurs a phenomenon that a picture displayed by the abnormal subpixel is brighter or darker than a picture displayed by the normal subpixel (the abnormal subpixel is unable to display preset brightness), so that a “moire” (mura) phenomenon occurs in the display picture of the display device, thereby degrading the display effect of the display device.
To solve the above problem, in addition to a source driver of the display device, a voltage compensation device may be generally added for performing the voltage compensation on the data voltage of the abnormal subpixels, so that the abnormal subpixel displays the preset brightness, and the mura in the display picture is eliminated.
In prior art, following steps are generally utilized to eliminate the mura in the display picture. Firstly, gray mura information in gray test picture is obtained and is stored in a storage module of a display module, and the gray mura information includes coordinate information and several voltage compensation tables. The coordinate information includes coordinates of all abnormal subpixels in the corresponding gray test picture, while each coordinate corresponds to one voltage compensation table, and each voltage compensation table includes a serial of data voltages and compensation voltages corresponding to the respective data voltages. Then, when the display device displays a picture, the voltage compensation device performs the voltage compensation on the abnormal subpixels in the display device according to the gray mura information stored in the storage module, so as to eliminate the mura in the display picture.
However, in an actual operation procedure, it is found that only general mura in the display picture can be eliminated by using the method in prior art, while a color mura generated when the display picture exhibits a specific color and brightness of region of the specific color is relatively high cannot be eliminated. For example, when the display picture exhibits a red color of high brightness, the red color mura in the display picture is conspicuous and can hardly be eliminated.
The reason why the color mura cannot be eliminated is that, when the voltage compensation is performed on the abnormal subpixels in the display device in prior art, it is only relied on the gray mura information acquired in the gray test picture. Since the color mura is not appeared in the gray test picture, voltage compensation information regarding the color mura is not included in the gray mura information, and thus the voltage compensation cannot be performed on the color mura generated in the display picture.
As can be seen from above, only the general mura in the display picture may be eliminated based on the voltage compensation method in prior art, while the color mura cannot be eliminated when the color mura is generated in the display picture, so that the display effect of the display device is degraded.